JP6305205B2 - Magnet rotor type motor and pump including the motor - Google Patents

Description

  The present invention relates to a motor used for, for example, a drainage pump, and more particularly to a magnet rotor type motor.

FIG. 9 shows an entire configuration of a conventional drainage pump, and FIG. 10 shows a main part including the motor.
The drainage pump has a pump housing 10 made of synthetic resin or the like, and a rotary blade 20 is provided in a pump chamber 12 of the pump housing 10. A lower cover 40 is attached to the top of the pump housing 10 via an O-ring 30. The lower cover 40 includes a lid portion 46 having an opening 48, and the shaft portion 22 of the rotary blade 20 extends to the motor side through the opening 48 and is connected to the shaft 82.

A stator assembly 60 is attached to the upper portion of the lower cover 40 and is covered with the upper cover 50.
The stator assembly 60 has a bobbin 62 molded with a mold resin 61, and a stator core member 66 is excited by a coil 64 wound around the bobbin 62.
A metal bearing cover 70 attached to the inside of the mold resin 61 has bearings 72 and 74 and supports the shaft 82 rotatably. A rotor member 80 is attached to the shaft 82 to constitute a motor.

A draining plate 90 is provided between the shaft 82 and the shaft portion 22. The draining plate 90 has a function of preventing water returning from the piping to the pump chamber 12 side from being ejected from the opening 48 to the motor side.
This type of drainage pump is also disclosed in the following patent document.

JP 2009-264317 A

However, in the conventional drainage pump motor structure as described above, the coaxiality of the bearings 72 and 74 depends on the component accuracy and the assembly accuracy at the press-fitting portions of the bearing cover 70 provided on both surfaces of the molded resin body. .
The coaxiality of the bearings 72 and 74 affects the inclination of the shaft 82 and appears as the coaxiality between the rotary blade 20 and the pump housing 10.
SUMMARY OF THE INVENTION An object of the present invention is to provide a motor that can easily achieve coaxiality between bearings and is excellent in assemblability.

In order to achieve the above object, a magnet rotor motor to which the present invention is applied includes a resin-molded stator assembly and a rotor assembly that holds a cylindrical magnet rotor that is electromagnetically driven to rotate by the stator assembly. A magnet rotor type motor for a pump comprising a solid body ,
Said stator assembly, Bei example a stator core member which are laminated, and the resin mold body formed by the stator core member molded with resin, and a central shaft attached to the resin molded body,
Before SL rotor assembly consists of a rotor central body having a central axis hole with a bottom through holding the magnet rotor,
By inserting the central shaft into the central shaft hole of the rotor central body, the rotor assembly is rotatably supported .
At the bottom of the central shaft hole of the rotor central body is provided with a thrust receiving plate with which the tip of the central shaft can abut,
Before Symbol a lamination thickness of the stator core members in the stator assembly, the distance from the lower surface of the stator core member and the center shaft tip L, also the distance of the height of the magnet rotor b, until the thrust receiving plate from the upper surface of the magnet rotor when the H, the deviation amount c of the magnetic center of the stator core member and the magnet rotor in the axial direction of the central shaft is formed so as to holds the following relation.
c = (L + a / 2)-(Hb / 2)
c> 0

The upper bearing of the rotor central body is disposed in a depressed state from the upper surface of the rotor central body .

  The rotor central body includes a flange portion having an outer diameter that is long enough to cover a rotor accommodating portion in the stator assembly.

  Furthermore, the rotor center body includes a mounting portion for connecting the rotating blades at the lower end.

  The magnet rotor type motor of the present invention includes a motor cover that covers the magnet rotor type motor, a rotary blade that is connected to the rotary output shaft, a pump housing that has a pump chamber that houses the rotary blade, and the pump housing And a housing cover that functions as a lid that covers the opening on the upper surface of the pump.

According to the magnet rotor type motor of the present invention, since the stator core member and the magnet rotor are attracted to each other by the magnetic force, the rotor assembly and the center shaft do not fall out of the stator assembly.
Therefore, additional fixing between the stator assembly and the central shaft is not necessary, and the assemblability of the motor itself or the assemblability of equipment (for example, a drainage pump) using the motor as another drive source is improved.

Sectional drawing of the magnet rotor type motor of this invention. Sectional drawing of a stator assembly. Sectional drawing of a rotor assembly. The side view of the drainage pump to which the motor of the present invention is applied. The top view of a drainage pump. AA sectional drawing of FIG. Explanatory drawing of a rotary blade. Sectional drawing of a rotary blade. Sectional drawing of the conventional drainage pump. Sectional drawing of the conventional motor.

  FIG. 1 shows a preferred embodiment of a magnet rotor type motor 100 according to the present invention. The motor 100 is composed of a stator assembly 120 and a rotor assembly 140 which are manufactured as separate assemblies.

As shown in FIG. 2, the stator assembly 120 has a rotor accommodating portion, and has a bobbin 122 integrally disposed in the resin mold body 121 on the periphery. A coil 124 is wound around the bobbin 122 and receives power from the lead terminal 125. The coil 124 excites the stator core member 126 on which the metal plates are stacked.
A central shaft 130 having a circular cross section is attached to the center of the resin mold body 121.
In addition, the center shaft 130 is attached by soft press-fitting in the present embodiment, but may be rotatable.

The rotor assembly 140 has a rotor center body 141 having a hollow cylindrical shape and a center shaft hole. A mounting portion 144 that is press-fitted into the shaft portion 210 of the rotary blade 200 is protruded from the lower end portion of the rotor central body 141, and a magnet rotor 146 is fixed to the upper outer side of the rotor central body 141.
Below the magnet rotor 146, a flange portion 142 for preventing water from entering the inside is provided. The flange portion 142 has an outer diameter sufficient to cover the rotor accommodating portion of the stator assembly 120.
Bearings 150 and 152 for the central shaft 130 are attached to the central shaft hole of the rotor central body 141. The upper bearing 150 is provided so as to be depressed by a predetermined depth from the upper surface of the rotor central body 141.
The bearings 150 and 152 are oil-impregnated sintered metal bearings impregnated with lubricating oil, but since the rotor center body 141 has the above-described structure, the lubricating oil that oozes out from the oil-impregnated sintered metal bearing is prevented. It does not flow out of the rotor center body 141, so that sufficient lubrication performance is ensured over a long period of time. The bearings 150 and 152 may be porous ceramic bearings impregnated with lubricating oil.
Further, a thrust receiving plate 160 is disposed at the bottom of the lower bearing 152.

In the process of assembling the rotor assembly 140 with respect to the stator assembly 120, the center shaft 130 of the stator assembly 120 is inserted into the bearing 150 and the bearing 152 of the rotor assembly 140.
At this time, the stacking thickness of the stator core member in the stator assembly is a, the distance from the lower surface of the stator core member to the tip of the central shaft is L (see FIG. 2), the height of the magnet rotor is b, and the upper surface of the magnet rotor is When the distance to the thrust receiving plate is H (see FIG. 3), the deviation c of the magnetic center between the stator core member and the magnet rotor in the axial direction of the central shaft is formed so as to satisfy the following relational expression.
c = (L + a / 2)-(Hb / 2)
c> 0
With such a configuration, the front end portion of the center shaft 130 abuts against the thrust receiving plate 160, and the stator core member 126 and the magnet rotor 146 are attracted by the mutual magnetic force, so that the rotor assembly 140 does not fall off from the center shaft 130.
Further, since the rotor assembly 140 attracts the stator assembly 120, the central shaft 130 can be prevented from being detached from the stator assembly 120.

It has a structure in which the gap G ₁ is formed between the bottom portion 121a and the flange portion 142 of the resin mold body 121 in this state. This gap G ₁ is set so as not to rotor assembly 140 from interfering with the resin mold body 121 during rotation. Further, the presence of the flange portion 142 prevents water from entering the motor 100.

4 is a side view of a drainage pump equipped with the motor of the present invention, FIG. 5 is a top view, and FIG. 6 is a cross-sectional view taken along line AA of FIG.
The drainage pump has a pump housing 10 made of synthetic resin, and a rotary blade 200 is provided in the pump chamber 12 of the pump housing 10. A synthetic resin housing cover (hereinafter referred to as a lower cover) 40 is attached to the upper portion of the pump housing 10 via an O-ring 30.
The lower cover 40 is detachably attached to the pump housing 10 by a snap fitting function using a snap fitting type locking claw 14 provided in the pump housing 10.
The lower cover 40 has a lid portion 46 that covers the upper surface of the pump housing 10, and an opening portion 48 through which the shaft portion 210 of the rotary blade 200 passes is formed at the center portion of the lid portion 46.

Here, details of the synthetic resin rotating blades provided in the drainage pump described in FIG. 6 will be described with reference to FIGS. 7 is an explanatory diagram of the configuration, and FIG. 8 is a cross-sectional view of FIG.
The rotary blade 200 has a shaft portion 210 at the top and a small diameter blade 220 at the bottom. The outer periphery is surrounded by a ring portion 230, and a large-diameter blade 240, an auxiliary large-diameter blade 250, and an inner protrusion 260 are formed therein.

The mounting portion 144 of the rotor assembly 140 described above is press-fitted into the shaft portion 210 of the rotary blade 200.
A motor 100 is mounted on the upper portion of the lower cover 40 and is covered with a synthetic resin motor cover (hereinafter referred to as an upper cover) 50. An upper portion of the upper cover 50 is provided with a mounting portion 52 for a mating member (not shown).
The upper cover 50 has a snap-fit type locking claw 54 and is attached to the lower cover 40 by a snap-fit function using the elasticity of synthetic resin.

In the motor 100 of the present invention, a structure in which the central shaft 130 on the stator assembly 120 side is taken in and surrounded by the synthetic resin rotor assembly 140 is adopted, and the stator core member 126 and the magnet rotor 146 are mutually connected. They are arranged to attract each other by magnetic force.
With this structure, no metal parts are exposed to the outside as a motor device, so that reliability and safety are improved, such as leakage from the motor device and prevention of electric shock, and additional fixing during assembly. No operation is required, and there is an advantageous effect in terms of manufacturing.

  In addition, although the case of the drainage pump was illustrated as a specific application example of the motor of the present invention, the motor of the present invention can be applied to various other fields or uses.

DESCRIPTION OF SYMBOLS 100 Motor 120 Stator assembly 121 Resin mold body 122 Bobbin 124 Coil 126 Stator core member 130 Center shaft 140 Rotor assembly 141 Rotor center body 142 Flange part 144 Mounting part 146 Magnet rotor 150, 152 Bearing 160 Thrust receiving plate 200 Rotary blade 210 Axis Part 220 Small-diameter blade 230 Ring part 240 Large-diameter blade 250 Auxiliary large-diameter blade 260 Inner protrusion G ₁ Gap a Stack thickness of the stator core member L Distance from the lower surface of the stator core member to the tip of the central shaft b Height of the magnet rotor H Magnet rotor Distance from top surface of thrust plate to thrust receiving plate c Deviation of magnetic center between stator core member and magnet rotor in axial direction of center shaft

Claims (5)

A magnet rotor motor for a pump , comprising: a resin-molded stator assembly; and a rotor assembly that holds a cylindrical magnet rotor that is electromagnetically driven to rotate by the stator assembly;
The stator assembly includes a laminated stator core member, a resin mold body formed by resin molding the stator core member, and a central shaft attached to the resin mold body,
The rotor assembly comprises a rotor central body having a bottomed central shaft hole that penetrates and holds the magnet rotor;
By inserting the central shaft into the central shaft hole of the rotor central body, the rotor assembly is rotatably supported.
At the bottom of the central shaft hole of the rotor central body is provided with a thrust receiving plate with which the tip of the central shaft can abut,
The lamination thickness of the stator core member in the stator assembly is a, the distance from the lower surface of the stator core member to the tip of the central shaft is L, the height of the magnet rotor is b, and the distance from the upper surface of the magnet rotor to the thrust receiving plate is H. The amount c of deviation of the magnetic center between the stator core member and the magnet rotor in the axial direction of the central shaft is formed so that the following relational expression is satisfied: c = (L + a / 2) − (H−b / 2) )
c> 0
Magnet rotor type motor characterized by this.   The magnet rotor type motor according to claim 1, wherein the central rotor body is provided with a bearing for making the central shaft rotatable. 3. The magnet rotor type motor according to claim 1, wherein the rotor center body includes a flange portion having an outer diameter larger than an inner diameter of a rotor housing portion in the stator assembly. The magnet rotor type motor according to any one of claims 1 to 3 , wherein the rotor central body includes an attachment portion for connecting a rotation output shaft at a lower end portion. The magnet rotor type motor according to claim 4 , a motor cover that covers the magnet rotor type motor, a rotary blade that is connected to the rotary output shaft, a pump housing that has a pump chamber that houses the rotary blade, A housing cover that functions as a lid that covers an opening on the upper surface of the pump housing.

Images